Process for the manufacture of detonating caps for mining and military purposes



NEW STfiTES smear QFFHCE.

WALTER FRIEDERICH, OF TROISDOBF, NEAR COLOGNE, GEREANY.

IPRQGESS FOR, THE MANUFACTURE OF DETONATING GAPS 30R MINING D MILITARY Patented Aug. 11, 11922.

PURPOSEQ.

1,424,4(5g, Specification of Letters Patent.

1T0 Erawtng. Application filed December15, 1920. serial No. 431,046.

To all whom it may concern:

Be it known that I, WALTER FRIEDERICH, Ph. D., a subject of the German Republic,

and resident of Troisdorf, near Cologne,

German have invented certain new and useful m rovements in the Processes for the Mann acture of Detonating Caps for Mining and Military Purposes (for which I have filed an application in Germany, July 27, 1918), of which the following is a specification.

This invention relates to the manufacture of detonating or blasting caps or cartridges for mining and military purposes of t e kind which are charged with nitro compounds upon the top of which is placed a priming of lead azide and on the lead azide is placed a loading of fulminate of mercury, a mixture of fulminate and potasslum 'chlorate, picrates, gun powder or other easily inflammable substances.

It has already been proposed to employ plinitroresorcin and its salts as complete or partial substitute for the fulminate of mercury in the above manufacture of blasting caps or other initial fuses (see specification to British Patent No. 20133, A. D. 1900). The results obtained have not been entirely satisfactory.

It has now been ascertained that lead trinitroresorcinate which results when hot solutions of nitrate of lead are mixed together with easily soluble trinitrotesorcinates is an admirable substitute for the fulminate of mercury. The lead trinitroresorcinate employed ma contain water of crystallization C H.(NO,, O Pbl-I O, or it may be dehydrated and the quantity required for one cap varies normally between 0.15 and 0.30 g.

The lead trinitroresorcinate may be stored for a much longer time than fulminate of mercury and may even in the dam state he brought in contact with zinc, iron, a uminium or other metals or their alloys without de teriorating or attacking the metals. It explodes without the addition of an oxy en carrier and does not retard the ignition ut quickly transmits the flame.

point of which lies at about 320330 C, so that its ignition is somewhat dificult. These objects in view are best attained by placing lea'd trinitroresorcinate on lead azide or mixing it therewith. It may be enclosed in a capsule such as are placed in safety blasting caps upon the initial charge in order to render it more efiective in action and safer in handling. v

It will thus be obvious that the employment of the lead trinitroresorcinate represents a great technical advance in the art.

The following may serve as examples for charges for detonating or blasting caps accordlng to the improved process. 0

Example 1: On a main charge of 0.9 g. of tetranitromethylaniline is placed 0.2 g. of lead azide and'on this 0.2 g. of lead trinitroresorcinate.

Example 2: On a main charge of 0.7 g. of nitopentaerythrite is placed 0.2 g. of lead azide and on this 0.2 g. of lead trinitoresorcinate.

It will be readily understood that I do not limit myself to the employment of the lead trinitroresorcinate in conjunction with the main charges mentioned or to the proportions stated as these may be varied within the ambit of the claims Without departing from the spirit of my invention or sacrificing any of its advantages.

What I claim as my invention and desire to secure by United States Letters Patent 1s:

1. The process for the manufacture of detonating caps and the like for mining and military purposes which consists in priming the ordinary main charge with lead azide and then placingjlead trlnitroresorcinate on said lead azide.

2. As a new article of manufacture a detonating cap for mining and military purposes consisting of the ordinary main charge, a priming of lead azide and a loading of lead trinitroresorcinate placed on said priming.

In testimony thereof I have hereunto set my hand in the presence of two subscribing witnesses.

DR. WALTER FRIEDERICH.

Witnesses JosEr SrEINBRfioER, AN'roN NORM. 

